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Full-Text Articles in Engineering
Analyses, Calibration And Validation Of Evapotranspirationmodels To Predict Grass-Reference Evapotranspiration In Thesenegal River Delta, Koffi Djaman, Hossein Tabari, Alpha B. Balde, Lamine Diop, Koichi Futakuchi, Suat Irmak
Analyses, Calibration And Validation Of Evapotranspirationmodels To Predict Grass-Reference Evapotranspiration In Thesenegal River Delta, Koffi Djaman, Hossein Tabari, Alpha B. Balde, Lamine Diop, Koichi Futakuchi, Suat Irmak
Department of Biological Systems Engineering: Papers and Publications
Study region: Grass-reference evapotranspiration estimation by the Penman-Monteithmethod (PM-ETo) requires a number of climate variables which are not always availableat all weather stations. Different alternative ETo equations have been developed and theirutilization for various local climate conditions requires analyses of their accuracy as com-pared to the standardized Penman-Monteith method. There is a significant lack of data andinformation on this topic in the Senegal River Delta (SRD). Study focus: The objective of this study was to evaluate, calibrate and validate six EToequations ((Trabert, Mahringer, Penman1948, Albrecht, Valiantzas1 and Valiantzas2) forthe SRD. Although all six equations showed good agreement with the PM-ETo …
Fuel Consumption Models For Tractors With Partial Drawbar Loads, Bryan Jeffrey Smith
Fuel Consumption Models For Tractors With Partial Drawbar Loads, Bryan Jeffrey Smith
Department of Biological Systems Engineering: Dissertations, Theses, and Student Research
Three models for predicting fuel consumption for agricultural tractors with partial drawbar loads were compared. Data were collected from eight John Deere tractors, JD 7230R (e23), 7250R (e23), 7270R (e23), 7290R (e23), 7290R (IVT), 8320R (16 speed), 8345RT (IVT), 8370R (IVT). The tractors were tested with 7 load levels per speed at four different travel speeds as close as possible to 4, 7.5, 10, and 13 km·h-1. The IVT tractors were operated in Auto mode and the geared tractors were shifted up three gears and throttled back to the same travel speeds as the IVT tractors. The 7 …
Evaluation Of A Hybrid Remote Sensing Evapotranspiration Model For Variable Rate Irrigation Management, J. Burdette Barker, Christopher M. U. Neale, Derek M. Heeren
Evaluation Of A Hybrid Remote Sensing Evapotranspiration Model For Variable Rate Irrigation Management, J. Burdette Barker, Christopher M. U. Neale, Derek M. Heeren
Department of Biological Systems Engineering: Papers and Publications
Accurate generation of spatial irrigation prescriptions is essential for implementation and evaluation of variable rate irrigation (VRI) technology. A hybrid remote sensing evapotranspiration (ET) model was evaluated for use in developing irrigation prescriptions for a VRI center pivot. The model is a combination of a two-source energy balance model and a reflectance based crop coefficient water balance model. Spatial ET and soil water depletion were modeled for a 10 km2 area consisting of rainfed and irrigated maize fields in eastern Nebraska for 2013. Multispectral images from Landsat 8 Operational Land Imager and Thermal Infrared Sensor were used as model …
Simulation Of Runoff Transport Of Animal Manure Constituents, Yang Wang, Dwayne R. Edwards, Tommy C. Daniel, H. Don Scott
Simulation Of Runoff Transport Of Animal Manure Constituents, Yang Wang, Dwayne R. Edwards, Tommy C. Daniel, H. Don Scott
Biosystems and Agricultural Engineering Faculty Publications
Runoff losses of land-applied animal manure constituents can adversely affect the quality of downstream waters. Reliable mathematical simulation models can help estimate runoff losses of animal manure constituents and identify management measures to reduce these losses. The objective of this study was to develop and calibrate an event-based simulation model to describe the runoff transport of solids (soil and manure particles) and nutrients (nitrogen and phosphorus) from areas treated with animal manure. The resulting model, consisting of linked hydrology, soil/manure transport, and nutrient transport components, is process-oriented and uses measurable parameters to the greatest degree possible. The three components of …